[Screening of periodontal and salivary parameters in patients with frequent acute exacerbation of chronic obstructive pulmonary disease]

Objective: To screen the risk factors of patients with frequent acute exacerbation of chronic obstructive pulmonary disease (COPD) by detecting the clinical indicators of periodontitis and the level of bacterial and inflammatory markers in saliva. Methods: Thirty-eight COPD patients in their stable period were recruited and detected from Beijing Chao-Yang Hospital,Capital Medical University during December 2016 to May 2017. The periodontal index were recorded. The levels of inflammatory factors in saliva samples were examined by using enzyme linked immunosorbent assay (ELISA). The bacteria composition in the saliva samples were identified by using 16SrRNA gene pyrosequencing. All patients were followed up and monitored for acute exacerbation of COPD for 12 months. The patients were divided into frequent acute exacerbation group (≥2 times/year, n=10) and non frequent acute exacerbation group (<2 times/year, n=28). Results: In univariate analysis, the patients' average age of frequent acute exacerbation group (69.0±7.3) was significantly older than that of non-frequent acute exacerbation group (61.8±8.3) (P=0.02). The numbers of remaining teeth ≤26 [100% (10/10)] was significantly higher and plaque index ≤2.5 (2/10) in frequent acute exacerbation group was significantly lower compared with the remaining teeth ≤26 [43% (12/28)] and the plaque index ≤2.5 [71% (21/28)] in non-frequent acute exacerbation group (P=0.02, P=0.01). The proportions of salivary inflammatory factors interleukin-6 (IL-6) level ≤60 ng/L (10%),C-reactive protein (CRP) level ≤1 550 μg/L (30%), matrix metalloproteinase-8 (MMP-8) level ≤140 μg/L (30%) and fibrinogen level ≤90 mg/L (30%) in frequent acute exacerbation group were significantly lower compared with salivary inflammatory factors IL-6 level ≤60 ng/L (71%),CRP level ≤1 550 μg/L (71%), MMP-8 level ≤140 μg/L (86%) and fibrinogen level ≤90 mg/L (71%) in non-frequent acute exacerbation group (P<0.05). The differences of relative abundances of salivary bacteria,such as species of Chloroflexi, Anaerolineae, Anaeroales, Corynebacteriales, Anaerolineaceae, Tissierellaceae, Leptotrichiaceae, Corynebacteriaceae, Leptotrichia, Moryella, Lachnoanaerobaculum and Corynebacterium between frequent acute exacerbation group and non-frequent acute exacerbation group were significantly different (P<0.05). In multivariate logistics regression analysis,the level of IL-6 >60 ng/L and the relative abundance of Corynebacteriales >0.2 had significant difference (P<0.05). Conclusions: The level of IL-6 and the relative abundance of Corynebacteriales might be the markers of frequent acute exacerbation in COPD patients.